AI tunneling through walls

maybe someone can help on this.
The AI on my track is tunneling through the walls if walls doesn´t exist. While this is just happening when touching walls in a sharp angle.
If AI touches walls in a dull angle, they hit like expected.

I had problems with AI going through walls on my track.
I made an invisible wall & put it 2 metres underground & about 10 metres high & it solved the problem.
Also if you do this you can uncheck collision on your other walls to save some FPS.
Cheers